Research firms IDC, ABI Research and Strategy Analytics have released their respective smartphone market data this morning and the numbers confirm that yes, Apple is the world’s leading smartphone maker in units (and revenue, for that matter), as previous surveys by Strategy Analytics and Nielsen pointed out. Furthermore, Apple is going after LG for the title of the world’s #3 maker of all phones. Even though their data includes preliminary estimates, Apple came on top with a record 20.34 million iPhones shipped, up from the 18.64 million iPhones shipped in the previous quarter and representing 142 percent unit growth over the year-ago quarter.

Apple’s achievement is even more surprising knowing they accomplished it with a one-year phone. Samsung shipped an IDC-estimated 19.2 million smartphones, a substantial increase over the 3.1 million units from the year-ago quarter, representing a 500 percent growth in units. In terms of market share, Apple held a 20.3 percent share of the smartphone market in the second quarter versus 19.2 percent for Samsung in the industry that shipped an IDC-estimated 110 million smartphones in the June quarter (ABI: 103 million). Samsung, which reported earnings today, also said it would stop reporting phone sales and forecasts for its mobile phones and tablets, citing competitive reasons. IDC explains Apple’s victory over Samsung:

Apple maintained its number four position overall but closed the gap on Top 5 competitors thanks to another record unit shipment quarter. The company easily posted the highest growth rate of the worldwide leaders despite the fact that its flagship iPhone 4 is now more than a year old. The triple-digit shipment volume growth allowed Apple to more than double its share when compared to the same quarter last year. Apple’s ability to bring its smartphone momentum to developing economies, where it’s less successful, will help dictate the company’s smartphone fortunes in future.

However, ABI Research senior analyst Michael Morgan comments

Although Apple’s 142% YoY growth placed it as number one this quarter, Samsung’s 500% YoY growth shows that going forward, the top smartphone OEM position is Samsung’s to lose.

Whether or not Apple remains the top smartphone vendor in the September quarter remains to be seen, but Samsung’s growth relative to Apple indicates that the Korean firm might dethrone Apple as soon as the next quarter. ABI says some 47 million Android smartphones were shipped in the second quarter, giving Google a 46.4 percent platform share. Samsung captured 34 percent of those Android shipments, HTC 23 percent and Sony Ericsson 11 percent. Note that HTC is the leading Android vendor in the US and the nation’s second-largest smartphone maker, according to Nielsen’s study from yesterday. Another interesting factoid…

When one looks at all of the handsets shipped during the quarter, which includes devices from entry-level dumb phones to high-end smartphones, Apple now has a 5.6 percent unit share of the cell phone industry globally, up from the five percent milestone from last quarter and 2.6 percent in the year-ago quarter. The company is now closing in on LG, the world’s #3 handset vendor, which in the July quarter held 6.8 percent of the global market for cell phones, an 18.9 percent decline from the 9.3 percent share in the year-ago quarter. The entire market grew by 11.3 percent overall and in all, ABI notes that RIM remains in a decline as their shipments fell 11 percent sequentially to 13.2 million smartphones. As for Motorola, they yesterday reported shipments of 4.4 million Android smartphones, not enough to make it on the list of the world’s top five phone vendors unit-wise.